Internal-combustion engine



L. M. wooLsoN INTERNAL COMBUSTION ENGINE Filed April 19, 1928 3 Sheets-Sheet 1 Jan. 6, 1931. L. M. WOOLSON 1,788,140

INTERNAL COMBUSTION ENGINE Filed April 19, 1928 3 Sheets-Sheet 2 Jan; 6, 1931. 1.. M. WOVOLSON 1,788,140

INTERNAL COMBUSTiON ENGINE Filed April 19, 1928 3 Sheets-Sheet 3 .Lz qzvszd MWJULEUM.

Patented den. 6 313i @FFl-CE LIONEL M. WOQLSON, 0E DETRQKT, MICHIGAN, ASSIGNGJR, T0 PACKARD MOTOR CAB, COMPANY, 0F DEIERUIT, MICHIGAN, A CORJPORATION' MICHIGAN rnrnnnnL-cortnusrion Enema Application filed April 19,

This invention relates to internal combustion engines. a I

One of the objects of the present invention is to provide a new method of operatlng an internal combustion engine.

Another object of the invention is to provide an internal combustion engine operating on a new cycle.

Another object of the invention is to provide an internal combustion engine operating on a cycle including an idle stroke.

Another object is to provide an internal combustion engine operating on a five-stroke cycle.

Another object is to provide an internal combustion engine characterized by extreme simplicity of construction.

Another object is to provide an internal combustion engine constructed of a relatively small number of parts.

Another object is to provide an internal combustion engine of the opposed piston type in which the pistons move in the same direction in the cylinder throughout a complete stroke of the engine.

Another-object of the invention is to provide an internal combustion engine of the opposed piston type in which the travel of the pistons on each stroke of the engine, except the idle stroke, is unequal.

Another object is to provide an internal combustion engine oil the opposed piston type having spaced cylinder ports in which only one of the pistons on the power stroke of the engine uncovers only one of the ports.

Another object is to provide an internal combustion engine of the opposed piston type in which one of the pistons remains substantially stationary during part of the engine cycle.

Another object is to provide an internal combustion engine of the opposed piston type in which each piston moves in substantially the same part of the cylinder during part of the engine cycle. 0

Another obyect of the invention is to pro vide a new method of making a piston.

Another object is to provide an internal combustion engine having a piston provided with means adapted to eliminate side thrust ices." Serial n6.'271,13e.

Other objects of the invention will appear from the following description taken in connection with the drawings forming a part of this specification, in which:

Fig- 1 is a view showing the development of the cams used in the engine of the present invention and diagrammatic views of a cylinder and the positions of the pistons therein corresponding to the points on the cams opposite which 1 they appear, the positions shown being the beginning of the power, ex haust, idle, intake andcompression strokes of the engine;

Fig. 2 is a vertical sectional view of the engine on line 2-2 of Fig. 3, the cams and pistons being shown in elevation;

Fig. 3 is a sectional view of the engine online 33 of Fig. 2;

Fig. at is a sectional view taken on line 4-4.

of Fig. 2;

Fig. 5 is a plan view of one of the pistons used in the engine of the present invention;

Fig. 6 is a sectional view of the piston on line 66 of Fig, 5, and

Fig. 7 is a partial sectional view of the piston showingthe head welded thereon and before the ring grooves are formed in tho pis-. ton.

Referring to the drawings, 10 represents generally a two cylinder internal combustion engine constructed in accordance with the present invention. As shown. the engine has a cylinder block 11 consisting of upper and lower cylinder portions 12 and 13 and interconnecting portions 14: joining the cylinder portions. A base 15 preferably formed integrally with the lower cylinder portion 13 provides means for supporting the engine on any suitable foundation or bed and apertures 16 are adapted to receive suitable fastening means for securing the engine in position.

Cylinder portion 12 is provided witha cylin derl? and cylinder portion 13 with a cylinder 18, each cylinder preferably extending the full length of the cylinder portions and being open at both ends. As shown, each cylinder is provided with an inlet port preferably consisting of a series of ports 19 at one side of the center of the cylinder and with an exhaust port preferably consisting of a series of ports 20 at the other side' of the center of the cylinder. The inlet port of each cylin- 5 der communicates with a passage 21 and the exhaust port of each cylinder with a passage 22 formed in the cylinder portions 12 and 13. Each of these passages preferably completely surrounds the cylinder in the zone of the ports and the intake passages conveniently extend to one side of the cylinder block and the exhaust passages to the otherside as shown. A

manifold 23 connects a carburetor, not shown, with each of the intake passages 21 15 and a manifold 2a connects each exhaust passage with a suitable mufiling device, not shown.

Rotatably mounted in cylinder block ll is a drive shaft 25 and, in the form shown, this shaft is journaled in the interconnecting portions 14 preferably midway between the cylinders 17 and 18 in suitable anti-friction bearings 26, Keyed or otherwise non-rotatably mounted on the tapered ends of the drive shaft 25 projecting outside the cylinder block opposed bearing surfaces 31. The development of these cams is clearly shown in Fig. 1. Each cylinder 17 and 18 is provided with no a pair of opposed pistons 32, each piston being preferably hollow and having proyect: ing from one end an extension of substmitially rectangular cross-section, preferably formed integrally with the piston and having spaced parallel arms 34 and 35-. The arm 35, preferahy longer than the arm 34, has an arcuate ottom surface 36, as shown, of substantially the same curvature as that of the outer wall of the piston. llotatably mounted between'arms 34 and on a shaft 37 supported at its ends in the arms is a beveled roller 38, and axially spaced from this roller 38 is another beveled rel-e333 rotatably mounted on a shaft 40 supported one end in the arm 33 as shown. These beveled rollers and 35 are adapted to engage the opposed bearing surfaces of cams 29 and 301 mactuate the cam wheels or to be actuated ther by as will presently appear.

Each piston assembly, including the int gral extension arms. is preterabiy produced a ,blanl. of solid metal. The portion of blank from which the pi, ton is produced is hollowed from the and opposite to the end from which the extension 33 projects the bolts 47 shown.

by any suitable machining process, this hollowing process being carried out so that the annular wall of the piston for a short distance from the open end is of greater thick ness than the wall of the remainder of the piston, this thicker portion being shown at 41 in Fig.-7 lhe open end of the piston is then closed'by a cover &2 permanently secured to the piston, preferably by welding, and the piston ring grooves 43 are formed in the thicker portion of the piston wall as shown. A vent 44' is provided for the piston preferably in the bottom wall thereof.

The alignment of each piston in its cylinder during operation of the engine is maintained by suitable guides in which the piston exten- SIOHS 33 are adapted to move. These guides are shown at 44 and each consists of an elongated member, substantially ll-shaped in transverse cross section as best shown in Fig. 4, the guiding surfaces being finished to provide a running fit,with the arm 35 of piston extension 33. As shown the guides at are spaced from the outer ends of the cylinders so as not to interfere with the pistons on their outward strokes, and each guide is provided with an arm 45 having attaching flanges 43 for securing the guides to the cylinder block in any suitable manner such as by means of A spark plug 48 is threaded into the wall of each cylinder pref crably at the center of the cylinder and connectecl through wiring l9 to a suitable distributor 50 preferably mounted on one end of drive shaft 25 within the cam wheel 28 as shown.

Power is suitably transmitted from the engine by means or a shaft 51 connected in any convenient manner to the drive shaft 25 or to one of the cam wheels 2'? or 28. In the form shown, the shaft 51 is provided with an annular flange 52 which is conveniently secured to cam wheel 2? by bolts 53.

The engine be lubricated by any suitable means or method, such as by means of force feed or splash system, or it may be lubricated by merely supplying lubricant to the inside of the cam wheels whence it will flow or be impelled by centrifugal forceduring operation of the engine through suitable passages,"not shown, provided in the cam wheels and cams, to roll rs, guides, pistons, cylinders and other parts requiring lubrication.

The engine cooled preferably by water, the cylinder wate jackets and connections, not shown, being 1 conventional design, although is appent that the engine may be cooled by air cl The operation of the engine will be clearly and more readily understood by referring Fig. of the drawings which shows the evelopment of the cams 29 and 3&- used i engine of the-present invention together w diagrammatic views of a cylinder and the position. of the pistons therein corresponding llt) 1,7ea14o 4 3 to the points on the cams opposite which they appear, the positions showinbeing the beginnlng of the power, exhaust, idle, intake, compression and power strokes of the engine in the order named beginning firom the top of F ig. 1. The drive shaft and cams of the engine having been rotated and an explosive charge having been drawn into the cylinder, the pistons at the beginning of the power stroke, or at the time when the charge is fired, will occupy the positions shown in position A of Fig. 1. On the power stroke of the engine both pistons will be moved apart or outwardly of the cylinder and the roller 38 carried by each piston extension will be forced against that portion of each cam corresponding to the power stroke of the engine between the points a and b of each, these cam portions a b bein preferably constant acceleration curves. n the power stroke, the left hand piston as shown inFig. 1, orthe piston moving toward the exhaust port, moves'outwardly of the cylinder until the exhaust port is completely uncovered while the right hand piston,-o'r the piston moving toward the inlet port, moves outwardly of the cylinder only so far as to maintain the inlet port completely closed, these positions of the piston at the end of the power stroke and at the beginning of the exhaust stroke being shown at position B elf-Fig.1. On the exhaust stroke of the engine the rollers 38 and 39 carried by the piston extension travel on that part of the cams between the points I) and o and as clearly indicated the left hand. piston remains stationary or substantially so during this stroke while the right hand piston is moved inwardly of the cylinder to the exhaust port. At the end of the exhaust stroke of the engine the pistons will occupy the positions shown in position C of Fig. l.

In order that the cylinder may now be filled with a fresh charge, it is necessary that both pistons be moved from the exhaust port to the inlet port, or from a position in which the exhaust port is between the istons to a position in whidh the inlet port is etween the pistons, and this is accomplished on the next stroke of the engine during which the rollers 38 and 39 move on that part of each pain between the points ,0 and l. Since during this stroke of the engine, no change takes place with respect to the working fluid and since the pistons are merely moved from one pos tion to another in the cylinder, this stroke is roperly termed an idle stroke of the engine.

uring this idle stroke, both pistons have sub stantially the same length of travel in the same direction and at substantially the same rate of speed from the positions occupied in position C of Fig. 1 with the exhaust port between the pistons, to the positions occupied in position!) with the inlet port between the pistons. On the next or intake stroke of the engine, the rollers 38 and 39' move on the cams between the points and e, and as 3 clearly indicated, the ri ht hand piston will remain stationary or su stantially so while the left hand piston moves toward the exhaust port until its head portion just covers that port. This movement of 'the left hand piston draws into the cylinder a fresh charge.

and at the end of this intake stroke or atthe beginning of the compression stroke of the engine the pistons will occupy the positions'shown in positionE of Fig.1.

On the succeeding or compression stroke, rollers 38 and 39 will move on that part of each cam between the points e and a, and as clearly indicated, both pistons will be moved toward each other or inwardly of the cylinder until they occupy the positions shown in position A. On this stroke the right hand.

piston has moved from a position on the right hand side of the intake port to a position 7 near the center of the cylinder while the left hand piston has moved only from a position in which it still covers the exhaust portto a position near the center of the cylinder.

Thus on this stroke, the pistons have different lengths of travel and move at diiierent rates of speed toward each other and toward the center of the cylinder. At the. end of this compression stroke the charge is fired by the spark plug and the pistons are forced apart or outwardly of thecylinder on the power stroke of the engine. The cycle is then repeated as has been described.-

While the operation ofthe engine has been described with reference to one cylinder only, it will be apparent that theother cylinder of the engine shown will operate on the same cycle and in the same way, the cylinders firing al.ternatelyand not at the same time,

aslwill be understood.

From the foregoing it will be seen that the engine o erates on a five-strolire cycle condifferent lengths of travel and on the exhaust and intake strokes, one of the pistons remains substantially stationary. It will also be noted that during the cycle, both pistons move successively in the cylinder between the inlet and exhaust ports, or in other words, the two pistons move on strokes that overlap during each cycle. This is true, however, in the form of the invention shown, only on the exhaust, idle and intake strokes. As has been described, on the exhaust stroke of the no i engine, the right hand piston moves inwardly from a position in which it just covers the inlet port, past the center of the cylinder to the' exhaust port; on the idle stroke, the right hand piston returns to a-position at the right of the inlet port and the left hand piston moves inwardly from a position at the left of the exhaust port past the center of the cylinder to the inlet port, and on the intake stroke, the left hand piston returns to a position in which it just covers the exhaust port. Thus both pistons move in the same part of the cylinder between the ports. 7

-The relatively small number of parts necessary to construct a complete engine in accordance with the present invention, exclusive of the carburetion and ignition systemsv and a few utility parts, andthe economy of manufacture resulting from such extreme simplicity of construction will-be apparent.

The engine has a ositive valve action with complete freedom om valve troubles of any kind and the spark plug is protected from the hot exhaust gases during the latter part of the exhaustistroke which will permit relatively high compression pressures to be maintamed.

* combination, a cylinder, 9. piston movable in While a two-cylinder engine has been shown and described, it will be understood that any desired number of cylinders. may

be employed. It will also be understood that the form of invention selected. for illustration and description is to be. considered a preferred form and that the invention is to be limited only by the scope of the appended claims.

Having thus described the invention, what is claimed and desired to be secured by Let ters Patent is:

1. In an internalcombust on engine, in

- the cylinder and means for moving the piston the cylinder and means for moving the pison an idle stroke of the engine.

2. In an internal combustion engine, in combination, a cyl1nder,a pair of pistons in tons in the same direction on an idle-stroke of the engine. v

3. In an internal combustion engine, in combination, a cylinder,a pair of pistons in the cylinder and means for moving the pistons substantially equally in the same direction on one of the strokes of the engine.

4. In an internal combustion engine, in

combinatioh, a-c'ylinder, a pair of pistons in the cylinder and means for moving the pistonssubstantially equally in the same directionon an idle stroke of the engine.

5. In an internal combustion engine, in

combination, 'a cylinder, a pair of pistons movable in the cylinder, the cylinder having a. combustion chamber between the plstons, and means causing the pistons to move substantially equally in the same direction on one of the strokesof the engine.

stroke 0 the engine.

6. In an internal combustion engine, in combination, a cylinder, a pair of istons movable in the cylinder the cylinder aving a combustion chamber between the pistons, and means causing the pistons to move substantiall equally throughout a complete movable in the cy inder, the cylinder having acombustion chamber between the pistons, and means for retaining one of the pistons substantially'stationary during a stroke of the engine.

9. In an internal combustion engine, in combination, a cyl nder, a pa r vof pistons in the cylinder, and means causing unequal trav-- el of the pistons on one of the strokes of the engine and equal travel on another stroke of the engine. J

10. In an integral combustion engine, in combination, a cylinder, aspair of pistons in the cylinder, and cam means causing unequal travel of the pistons on one of the strokes of the engine and equal travelon another-stroke or the engine.

11. In an internal combustion engine, in combination, a cylinder, 9. pair 01' pistons in the c linder, and means causing unequal travel 0 .the pistons on one of the strokes and equal travel on anidle stroke of the engine.

12. In an internal combustion engine, in

combination, a cylinder, a pair of pistons in the cylinder, and means causing unequal travel of the pistons on the intake, compression, power and exhaust strokes and equal travel on an idle stroke of the engine.

13. In an internal combustion engine, in

combination, a cylinder, a pair of pistons in the cylinder and means causing the pistons to be separated on the power and inlet strokes of the engine, to be brought together on the compression and exhaust strokes, and to be moved substantially parallel'on an idle stroke.

14. In an internal combustion engine, in combination, a cylinder, a pair of pistons in the cylinder, and cam means causing unequal travel of the pistons on the intake, compression, power and exhaust strokes of the engine and equal travel on an idle stroke of the en- 15. In an internal combustion engine, in combination, a cylinder having spaced ports, a pair of pistons in the cylinder and means causing each piston to move in substantiallythe same part of the cylinder between the ports.

16.In an internal combustion engine, in combination, a cylinder having spaced ports, a pair of pistons in the cylinder, and means part of the cylinder on a stroke 0. theengine and movement of the other piston in substantially the'samepart of the'cylinder on another stroke of the engine; 7 v

.17: In an internal combustion engine, in combination, a cylinder having spaced'ports, a pair of pistonsin the cylinder, and means causing movement of .cach piston in the same predetermined part of the'cylinder on suecessive strokes of the engine.

18. In an internal combustion engine, in combination, a cylinder having spaced ports, a pair of pistons in the cylinder and means causing movement of one of the pistons in a part of the cylinder on the exhaust stroke of the engine and movement of the other iston in substantially the same part of the cy inder on the intake stroke of the engine.

19. In an internal combustion engine, in combination, a cylinder having spaced ports, a pair of pistons in the cylinder and means causing movement of one of the pistons ina part of the cylinder between the ports on a stroke of the engine and movement of the other piston in substantiallythe same part of the cylinder between the ports on another stroke of the engine.

20. In an internal combustion engine, in combination, a cylinder having spaced ports, a pair of pistons in the cylinder and cam means causing movement of one of the pistons in a part of the cylinder-on the exhaust stroke of the engine and movement-of the other piston in su stantially the same part of the cylinder on the intake stroke of the engine.

21. In a multi-cylinder internal combustion engine, in combination, a plurality of cylinders, a piston movable in each cylinder and means for moving the pistons on an idle stroke of the engine.

22. In a multi-cylinder internal' combustion engine, in combination, a plurality of p cylinder having an exhaust-port, a piston re cylinders, a pair of pistons in eachcylinder,

eachmylinder having a combustion chamber between the pistons, and means comprising a plurality of cams causing the pistons in each cylinder to inoilc substantially equally in the same direction on one 0mm strokes of the engine.

24. In a multi-cylinder internal combustion engine, in combination, a plurality of cylinders, a pair of pistons in each cylinder, and means comprising a plurality of cams causing unequal travel of the pistons in each cylinder on one of the strokes of the engine.

v25. In a multi-cylinder internal combustion engine, incombination, a plurality of cylinders each having spaced lnlet and exin each cylinder, one piston in each cylinder moving to uncover one of the ports and the otherpiston in each cylinder moving toward but not uncovering the other port on a stroke of the engine. I V

26. In a multi-cylinderinternal combustion engine, in combination, a plurality of cylinders, a pair of pistons movable in each cylinder, and cam means causing unequal travel of the pistons in each cylinder on one of the strokes of the engine and equal travel on another stroke of theengine.

27. In a multi-cylinder internal combustion engine, in combination, a plurality of cylinders, a pair of pistons in each cylinder, and means comprising a. plurality of cams causing unequal. travel of the pistons in each cylinder on the intake, compression, power idle stroke of the engine.

28. In a multi-cylinder internal COmbIlS- tion engine, in combination, a plurality of cylinders having spaced ports, a pair of pistons in each cylinder and means comprising a plurality of camscausing movement of one of the' IJlStOIlSlH a part of each cylinder between the ports on a stroke of theehgine and movement of the other piston insubstantially the same part of the cylinder between the ports on another stroke of the engine.

29. In an internal combustion engine, a cylinder having an inlet port, a piston reclprocable in the cylinder, said piston controlling the charge admission through the inlet port, and means associated with the piston causing uncovering of the port on a1- ternate piston strokes and maintaining the piston stationary for a period after uncovering the port.

3 0. In an internal combustion engine, a

ciprocable in the cylinder. said piston controlling the passage of exhaust through the exhaust port, and meansassociated with the piston causing uncovering of the exhaust port on alternate piston strokes and maintaining the piston stationary for a period after uncovering the port. j

31. In an internal combustion engine, a cylinder having spaced inlet and exhaust ports, a pair of reciprocable pistons in the cylinder, one of said. pistons controlling the inletport and the other of said pistons controlling the exhaust port,'and means causing each of's'aid pistons to uncover its respec-.

tively controlled port on alternate strokes, each piston being maintained stationary for a period after uncovering its respective port.

32. In an internal combustion engine, a cylinder, a pair of pistons in the cylinder, andmeans causing said pistons to be moved and stopped in a manner efiecting fivestrokes, one of said strokes being an idle stroke.

In an internal combustion engine, a cylinder, a pair of pistons, and means for causing said pistons to move in an idle stroke intermediate the exhaust and intake strokes..

34. The method of operating an internal combustion engine having a working chamber, comprising opening the chamber to a source of fuel supply, then expanding the chamber to thereby draw in a charge of ex- I plosive mixture, then closing the expanded chamber, then contracting the chamber and thereby compressing the charge therein, then firing the charge in the chamber and thereby again expanding the chamber, than opening the chamber, to atmosphere, then again contracting the chamber to thereby exhaust the burnt gases therefrom, then closing adjacent the exhaust port at the completion of the exhaust stroke.

38. The method of operating an internal combustion en ine comprising, introducing a charge of explosive mlxture into an engine cylinder, then compressing the charge therein, then firing. the charge in the cylinder, then exhausting the greater part of the burnt gases from the cylinder, and then trapping a portion of the burnt gasesin the cylinder and moving the entrapped gases from one part of the cylinder to another Without substantially expanding or contracting said gases, to be mixed'with the succeeding incomin charge.

In testimony whereo I aflix my signature.

LIONEL M. WOOLSON.

the chamber, and then maintaining the the chamber for the succeeding charge.

35. The method of operating an internal combustion engine having a working cham ber, comprising opening the chamber to an source of fuel supply, then expanding the chamber to, thereby draw in a charge of explosive mixture, then closing the expanded chamber, then contracting the chamber and thereby compressing the charge therein, then firing the charge in the chamber andthereby again expanding the chamber, then opening the chamber to atmosphere, then again contracting the chamber to thereby exhaust the burnt gases therefrom, then closin the chamber, and then maintainin the c amber in closed and-contracted con ition and moving it from one zone to another until the opening of'the chamber for the succeeding charge.

36. The method of operating an internal combustion engine having a Working chamber formed Within the cylinder comprising opening the chamber in one part of the cylinder to a source of fuel supply, expandin the chamber while open to the fuelsource to raw in a charge, closing the expanded chamber, contracting the chamber to compress the charge therein, firing the compressed charge and thereby expanding the chamber, opening the chamber to atmosphere in a part of the cylinder remote from the charge opening, contractingthe chamber While open to atmosphere, closing the chamber, and moving the contracted chamber to a position for repeating the cycle.

37 In a five-stroke cycle internal combustion engine,-a cylinder having spaced inlet and exhaust ports, a pair of reciprocable pis tons in the cylinder, and means for causing said pistons to be positioned immediately adjacent opposite sides of the'intake port atthe beginning of the intake stroke, and causing 

